Electric furnace



Dec. 18, 1928.

O. A. COLBY ELECTRIC FURNACE Filed OGt a w w mum mun -fififin INVENTOR Ora A. Ca/y ATTORNEY Patented Dec. 18, 1928.

UNITED STATES PATENT OFFICE.

ORA A. COLBY, OF MANSFIELD, OHIO, ASSIGNOR TO WESTINGHOUSE ELECTRIC do MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRIC FURNACE.

My invention relates to electric furnaces and particularly to means for supporting resistor members in electric furnaces of the resistance type.

6 An object'of my invention is to provide a support for resistor members that shall be simple, efficient and relatively inexpensive, and that shall support a set of resistors from one plane only of a wall of the furnace.

Another ob ect of my invention is to provide a resistor support in which registering and interlocking refractory insulating blocks are disposed on a vertical supporting member.

Another ob'ect of my invention is to provide efficient eating e ements for rectangular, pit and tank furnaces.

Other objects of my invention will be ap parent from the disclosure.

In practicing my invention according to the form shown in the accompanying drawing, I provide supporting rods suspended from the walls of an electric furnace. Each rod supports a plurality of registering and interlocking refractory insulating members. When the insulating members are assembled on each rod, they constitute an insulating supporting means for resistor members.

In the drawings,

Figure 1 is a view in vertical section, of an electric furnace embodying my invention, the section being taken transversely of the heating elements.

Fig. 2 is a view in vertical section, of the electric furnaceshown in Fig. 1, the section being taken in a direction parallel to the heating elements.

Fig. 3 is a view showing a cross section of my improved supporting means.

Fig. 4 is a perspective View of one of the refractory insulating members embodying my invention.

Referring to the drawings, a furnace 10. that is rectangular in shape, has a heating chamber 12, top and bottom walls 13 and 14 and side walls 15, the walls being made of suitable refractory material. One o'f-the side walls has an opening 16, as shown in Fig. 2, for the purpose of permitting the charging of the furnace with material to he heat-treated.- The opening 16 may be closed by any closure means commonly used in the art.

For the purpose of heating the furnace, 5b resistor elements 18 are provided. The reloops and are supported by a. plurality of vertically disposed-insulating. supports 20 that are suspended from hooks 22, the hooks 22 being. permanently secured to the side walls of the furnace by means of prongs 23 integral therewith and extendin into the side walls. Each support comprises a supporting rod. 25 that may be made of nichrome, an alloy comprising nickel and chromium, and a plurality of blocks 27 that are preferably stock porcelain insulators and that are mounted on the rod 25 and are supported thereby. The blocks 27 are preferably of substantially rectangular shape as best shown in Fig. 4.

Each rod 25 has an eye 28 at its upper end for .tlie purpose of engaging the hook 22 to be supported thereby, and at its lower end, it has suitable means for supporting the blocks 27, a convenient form of such means beinv a nut 30. A vertical hole 32 is providec in the block 27 through which the rod 25 extends. A groove 35' is provided in the upper side and a groove 36 in the lower side of each block. The grooves are shown in the drawing as being in different vertical planes onopposite sides of.

the hole 32 and each is adapted to receive a portion of a resistor 18. By'locating the grooves 35 and 36 in such planes, a pair of resistors may be engaged by each support and these resistorswill balance, so as to aid in maintaining the blocks in their proper positions. Each block is provided also with a projection 38 on its upper face and with a recess 40 onits lower face each extending across the width of the block." The recess 40 of one'block is adapted to receive the projection 38 of an adjacent block for the pur-v pose of locking the blocks in their proper relative positions.

As is best shown in Fig. 3, when the blocks 7 are placed on the rod 25 and the projections 38 and recesses 40 of adjacent blocks are placed in registering relation, the upper face of one block will engage the lower face or surface of an adjacent block. In such relation, the grooves 36 and the grooves 35 will cooperate with the top face and the bottom face, respectively, of adjacent blocks to provide laterally closed spaces in which portions of the resistor 18 may be located. The nuts 30 may be so adjusted that the grooves 35 and 36 of correspondingly a1"- ranged blocks of separate supporting members 20 will be in horizontal alinement.

\Vhen the blocks 27 are in position on rods 25; the nuts 30 in clamping positions on the lower ends of the rods and the eyes of the rods in engagement with the hooks 22 to support the columns of insulating blocks and the resistors located therein, the blocks 27 will be substantially in vertical alinement. The columns of blocks may be placed in contact with side walls 15 to further aid in sisters vertically.

iVhile l have shown hooks for supporting the columns, it is obvious that other well known supporting means might be used.

The construction embodying my invention thus provides a resistor for an electric furnace or other device, that is supported at, or suspended from, a single point of a wall or from a plurality of points lying in a single plane. The resistor-supporting means is, therefore, independent of relative movements of different portions of a furnace wall.

The heating unit comprising the resistor member, the refractory blocks and the metal rod and nut, may be built up outside of a furnace, and located in its proper operative position in the furnace. chamber by simply hooking the upper ends 28 of the rods over the alined supporting members 22.

While I have shown and described, for purposes of illustration, a specific form of my invention it may, of course, be embodied in other forms without departing from its spirit and scope, as set forth in the appended claims.

I claim as my invention:

1. in an electric heating furnace having walls of refractory insulating material. the combination of a plurality of securing members secured to said walls, supporting rods removably supported upon said securing members, av plurality of blocks of refractory insulating material supported by each of said rods, each of said blocks having grooves therein, and a pair of looped resistor members positioned in said grooves.

2. An electric furnace comprising, in com bination, walls of refractory insulating material inclosing a heating chamber, hooks secured to the walls of said chamber, metallic rods having eyes for engaging said hooks to vertically suspend said rods, a plurality of columns of insulating blocks, each column having a hole for receiving one of said rods, means at the bottom of the rod to secure said blocks in suspended position thereon,

a pair of resistor members supported by said blocks, adjacent blocks having coniplementary face grooves to form seats for said resistor members.

3. An electric furnace comprising, in combination, Walls of refractory insulating material inclosing a heating chamber, hooks secured to the walls ofsaid chamber, metallic rods vertically suspended from said llOOks, a plurality of columns of insulating blocks, each column having a vertical hole for re ceiving oneof saidrods, means at the bottom of the rod to secure said blocks in suspended position thereon, resistor members supported by said columns, adjacent blocks having complementary face grooves to form horizontal seats for a resistor member, the horizontal seat-s being disposed in alinement and adjacent blocks having interlocking means to maintain them in registering position.

4. In an electric furnace, the combination witha wall, and a plurality of alincd and spaced supporting members extending from said wall, of a heating unit suspended from said supporting members and comprising an extended resistor member, sets of refractory supporting blocks for the rc sistor, and metal suspension rods extending through the refractory supporting blocks and depending from the supporting members.

5. In an electric furnace, means for supporting a resistance element comprising a support secured to the side wall of said furnace and projecting from the face thereof, a plurality of insulating blocks pivotally suspended from said support, and means on adjacent faces of said blocks for engaging and spacing adjacent convolutions of said resistance element.

6. An electric furnace having walls of refractory insulating material enclosing a heating chamber, a vertically extending rod. means for supporting said rod in spaced re lation with a chamber side wall, a plurality of superposed blocks of insulating material. means for engaging portions of a resistance element between said blocks, and means for supporting said blocks in operative relation upon said rod.

7. In an electric furnace, a vertical metallic support, a column of insulating blocks mounted thereon and supported thereby, means formed in the adjacent faces of said blocks for engaging and spacing the convolutions of a resistance element, and means for preventing relative axial movement between said blocks.

In testimony whereof, I have hereunto subscribed my name this 22 day of Sept. 1926.

ORA A. COLBY.

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